City of Fallen Angels

The vampire Camille Belcourt wants Simon by her side, and he moves in with Jordan Kyle, a bandmate who's a werewolf. Jace dreams of killing Clary and pulls away from her. Lilith, mother of demons, draws a rune in Jace's blood and takes control of him. At Jocelyn and Luke's engagement party, Jace brings Clary to Lilith, who wants to use Simon to raise Sebastian. Simon bites Sebastian. Clary cuts the rune binding Jace, and Simon's Mark of Cain destroys Lilith. But Jace is forced to finish the ritual, and Sebastian is alive at the end.

1. ChangeJace becomes the Owl

   In the book, Lilith controls Jace through a rune drawn in his blood. On the show, she turns him into the Owl, a killer who acts without remembering any of it.

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2. ChangeWho takes down Lilith

   In the book, Simon's Mark of Cain turns on Lilith at the climax. On the show, the final win over her goes to Isabelle, using heavenly fire.

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3. ChangeMaureen exits early

   In the book, Maureen, a fan of Simon's band, becomes a vampire and plays a big part. On the show, she drops out during S1.

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